The conventional voltage boosting circuit employing a transformer, diode and condenser is very difficult to miniaturize by integrated circuit techniques. Therefore, the space requirements of the conventional voltage boosting circuit make it unsuitable for use where small size is required, for example in a wristwatch or hand held calculator. Furthermore, the cost of the circuit elements comprising a transformer and diode is high so that the cost of an electronic watch or calculator utilizing the voltage boosting circuit is correspondingly high.